The effects of endogenous opioids and cortisol on thyrotropin and prolactin secretion in patients with Addison's disease

This study assessed the controversial role of endogenous opioids and cortisol in the regulation of TSH and PRL secretion in humans. Seven euthyroid male patients with Addison's disease were studied four times, with an interval of 1-3 months, as follows: 1) during normocortisolism [graduated infusion of hydrocortisone, 0.4 mg/kg, over 19.5 h]; 2) normocortisolism and coadministration of naloxone, at 25 microg/kg x h during the last 6.5 h; 3) hypocortisolism (24 h withdrawal of hydrocortisone, followed by 19.5 h saline infusion); and 4) hypocortisolism plus naloxone administration. The TSH and PRL levels were measured every 15 min, from 0800-1530 h. A TRH test was performed at 1300 h and 1400 h (10 microg and 200 microg of TRH, respectively). The mean TSH level increased significantly during hypocortisolism, compared with normocortisolism (1.78 +/- 0.04 vs. 0.84 +/- 0.02 mU/L; P < 0.001). The administration of naloxone suppressed the TSH levels during hypo- and normocortisolism (1.78 +/- 0.04 vs. 1.50 +/- 0.03 and 0.84 +/- 0.02 vs. 0.61 +/- 0.02 mU/L, respectively; P < 0.001). During hypocortisolism, the TSH responses to small and high doses of TRH were significantly higher than during normocortisolism (P < 0.02). Naloxone had no effect on the TSH responses to TRH, neither during hypo- nor during normocortisolism. The mean PRL level increased significantly during hypocortisolism, compared with normocortisolism (5.8 +/- 0.4 vs. 3.6 +/- 0.2 microg/L; P < 0.001), and naloxone induced an increase in PRL levels both during hypo- and normocortisolism (7.1 +/- 0.7 vs. 4.7 +/- 0.5 microg/L, respectively; P < 0.01). The PRL responses to TRH were similar during hypo- and normocortisolism and without any change during opioid receptor blockade. In conclusion, cortisol suppressed basal TSH and PRL secretion and reduced the sensitivity of the thyrotrophs to TRH, without affecting the PRL response to TRH. Our results suggest that endogenous opioids act at the hypothalamic level to stimulate TSH secretion and to suppress the PRL secretion, but these results argue against an essential role of endogenous opioids in the physiological regulation of TSH and PRL secretion in humans.

Biochemical markers of bone metabolism in benign human osteopetrosis: a study of two types at baseline and during stimulation with triiodothyronine

Biochemical markers of bone remodelling were used to evaluate bone turnover in two types of autosomal dominant osteopetrosis (ADO) at baseline and during stimulation with triiodothyronine (T3). Eight patients with Type I (aged 23-61 years, mean 40.4 years) and nine patients with Type II ADO (aged 20-49 years, mean 32.8 years) were compared with 10 normal controls (aged 22-54 years, mean 35.4 years). The participants were treated with 100 microg T3 daily for 7 days and followed for a total of 16 weeks. Serum concentrations of T3 increased and corresponding suppression of TSH was observed in all participants. Both formative and resorptive bone markers were normal at baseline. After stimulation with T3, a significant increase was seen in all groups for the formative markers used. Secondary increments were observed at the end of the observation period for all groups, indicating activation of bone remodelling. A variety of resorptive markers was assessed, but no differences between patients and controls were seen. After stimulation, highly significant responses were found in all parameters in all groups, in accordance with stimulation of existing resorptive cells. However, no secondary increments were seen at the end of the observation period. A more pronounced response was found in crosslinks-related assays. The study demonstrates that it is possible to stimulate bone resorptive and formative cells with thyroid hormones in both types of ADO. Moreover, it indicates that the remodelling process is activated by a short course of T3 treatment.

Lack of effect of the dopamine D1 antagonist, NNC 01-0687, on unstimulated and stimulated release of anterior pituitary hormones in males

Dopamine in humans inhibits the secretion of luteinizing hormone (LH), follicular stimulating hormone (FSH), thyroid stimulating hormone (TSH) and prolactin (PRL), and is a stimulator of growth hormone (GH) secretion. Dopamine-D1 receptor stimulation with fenoldopam increases basal PRL levels, suppresses TSH, and increases gonadotropin releasing hormone (LHRH) induced LH release. We have investigated the effect of a dopamine D1-receptor antagonist, NNC 01-0687, on the secretion of anterior pituitary hormones. In 8 healthy males NNC 01-0687 and placebo were administered orally in a double-blind placebo controlled cross-over study for three days with a wash-out period of 14 days. Hormonal responses (PRL, LH, FSH, GH, TSH, thyroid hormones and testosterone), unstimulated and LHRH/TRH stimulated, were studied on days 1 and 3. No significant difference (p > 0.05) between placebo and active periods was found neither in unstimulated nor in stimulated hormone concentrations expressed in absolute values, percent change of before, incremental values and area under the curve. These results suggest that the neuronal DA-D1 activity is not activated during basal conditions in healthy male subjects.

Pulsatile luteinizing hormone secretion in patients with Addison's disease. Impact of glucocorticoid substitution

The physiological and pathophysiological role of cortisol in pulsatile LH release was investigated in 14 patients (5 men, 6 premenopausal women, and 3 postmenopausal women) with Addison's disease. The explicit effect of cortisol in relation to the effect of corticotropin-releasing factor (CRF), ACTH, and opioids was ensured by hypo-, normo-, and hypercortisolism. Hypocortisolism was obtained by 24-h discontinuation of hydrocortisone (HC) followed by 23-h saline infusion. Eucortisolism was secured by infusion of HC (0.5 mg/kg) over 23 h. Stress-appropriate hypercortisolism was obtained by infusion of HC (2.0 mg/kg) over 23 h, preceded by treatment for 5 days with dexamethasone (1.5 mg/day). To imitate the normal diurnal rhythm for serum cortisol, HC was infused in graduated doses. Blood sampling was performed every 10 min during the last 10 h of the study period, followed by a LH-releasing hormone test (5 microg, i.v.) and a TRH test (10 microg, i.v.). In pre- and postmenopausal women, the mean LH level and the LH pulsatility pattern were similar on the 3 occasions. In contrast, the mean LH level in men was significantly reduced during hypocortisolism compared to that during eucortisolism (3.26 +/- 0.68 vs. 4.49 +/- 0.83 U/L; P < 0.05) and was associated with a clear decrease in LH pulse amplitude (1.09 +/- 0.33 vs. 1.96 +/- 0.53 U/L; P < 0.05). During high doses of glucocorticoids, the mean LH level in men was significantly lower than that during eucortisolism (3.81 +/- 0.88 vs. 4.49 +/- 0.83 U/L; P < 0.05). In both men and women, the mean PRL levels increased significantly (P < 0.05) during hypocortisolism, whereas high glucocorticoid doses suppressed the mean PRL level (P < 0.05). The LH and PRL responses to LH-releasing hormone and TRH were, however, similar during low, medium, and high cortisol levels in both men and women. In conclusion, our data suggest that the attenuation of pulsatile LH secretion in men during hypo- and hypercortisolism is due to variations in the hypothalamic opioid activity secondary to alterations in serum cortisol levels. A higher level of opioid receptor activity in men than in low estrogen women may explain the gender differences.

Pulsatile thyrotropin secretion in patients with Addison's disease during variable glucocorticoid therapy

The inhibitory action of physiological to pathophysiological serum cortisol levels on TSH secretion were investigated in 12 patients with Addison's disease on 3 occasions. 1) In continuation of the conventional hydrocortisone (HC) substitution, a medium dose of HC (0.5 mg/kg) was infused over 23 h. 2) After 24-h withdrawal of HC, the patients had placebo infusion over 23 h. 3) After 5 days of dexamethasone (1.5 mg/day), a high dose of HC (2.0 mg/kg) was infused over 23 h. Blood sampling was performed every 10 min during the last 10 h of the study period, followed by a TRH test (10 micrograms, iv), To mimic the normal diurnal rhythm for serum cortisol, HC was infused in graduated doses, and during medium dose infusion, the serum cortisol level and the TSH pulsatility pattern were similar to those seen in normal controls. The TSH mean level was 1.0 +/- 0.5 mU/L during medium doses of HC, increasing significantly (P < 0.05) to 2.0 +/- 1.6 mU/L during the low cortisol state and was significantly (P < 0.05) suppressed to 0.4 +/- 0.2 mU/L during high doses of glucocorticoids, when the pulse frequency was also significantly reduced (P < 0.01). Together with a dose-dependent inhibitory action of glucocorticoids on the TSH response to TRH, our data indicate that even physiological serum levels of cortisol have an influence on endogenous TSH secretion, probably caused by regulation of the pituitary sensitivity to TRH.

Collagen metabolism in two types of autosomal dominant osteopetrosis during stimulation with thyroid hormones

In order to investigate collagen metabolism in two different types of autosomal dominant osteopetrosis (ADO), eight patients with type I (aged 23-61 years, mean 40.4 years) and nine patients with type II ADO (aged 20-49 years, mean 32.8 years) were compared with ten normal controls (aged 22-54 years, mean 35.4 years). The subjects were treated with 100 micrograms of triiodothyronine (T3) daily for 7 days and followed for a total of 4 weeks. Serum T3 increased in all subjects and a corresponding suppression of thyroid-stimulating hormone (TSH) was observed. Serum carboxy-terminal propeptide of type I collagen (S-PICP) in the control and type I groups showed no difference at baseline, whereas type II was lower than controls (p < 0.01). No significant alterations following stimulation were observed in any of the groups. Serum BGP (osteocalcin) values in the two patient groups were insignificantly lower than controls both at baseline and throughout the study. Following stimulation, a significant response was seen in the three groups (p < 0.001). The increases during the treatment period (delta values) for controls, type I and type II were 47.6% (p < 0.01), 51.7% (p = 0.05) and 34.8% (NS), respectively, with no difference between the groups. Serum bone-specific alkaline phosphatase (S-ALP) was not different between the groups and no alterations were observed in relation to treatment. The serum N-terminal propeptide of type III collagen (S-PIIINP) showed no difference at baseline between type I and controls but was significantly higher (p < 0.003) in type II than in the controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Dopaminergic inhibition of pulsatile luteinizing hormone secretion is abnormal in regularly menstruating women with insulin-dependent diabetes mellitus

OBJECTIVE

To examine the influence of low doses of dopamine (DA) (0.4 micrograms/kg per minute), on the secretion pattern of LH.

DESIGN

Prospective randomized, single blind, placebo-controlled crossover study with infusion of DA or placebo in the follicular phase in regularly menstruating women with insulin-dependent diabetic mellitus (IDDM) and controls during 9.5 hours.

SETTING

Department of Endocrinology, Odense University Hospital, Odense, Denmark.

PATIENTS

Eight regularly menstruating IDDM women and eight controls.

MAIN OUTCOME MEASURES

Mean LH, LH pulse amplitude, and LH pulse frequency.

RESULTS

During placebo infusion no significant differences in basal LH values, pulse amplitude, and pulse frequency were seen between IDDM women and controls. In diabetics, basal LH levels and pulse amplitude decreased significantly during DA infusion (3.1 +/- 1.2 mIU/mL (conversion factor to SI unit, 1.00; mean +/- SD) and 0.9 +/- 0.3 mIU/mL, respectively) compared with placebo (4.5 +/- 1.1 and 1.2 +/- 0.4 mIU/mL, respectively). In normal women no significant changes were observed (basal LH 3.0 +/- 1.8 versus 3.2 +/- 1.6 mIU/mL and pulse amplitude 1.6 +/- 0.6 versus 1.5 +/- 0.9 mIU/mL). The LH pulse frequency during DA infusion was not different from placebo in either normal (9.0 +/- 2.7 versus 10.3 +/- 4.0) or diabetic women (11.8 +/- 2.1 versus 10.9 +/- 1.8).

CONCLUSION

These results suggest that diabetic women are more sensitive to a small increase in peripheral DA concentration. An abnormal permeability of the blood-brain barrier in IDDM patients could explain a greater exposure of the hypothalamic structures, regulating the pituitary gonadotropin hormone secretion.

Autosomal dominant osteopetrosis: bone mineral measurements of the entire skeleton of adults in two different subtypes

Bone mineral content (BMC) and density (BMD) were measured by dual-energy X-ray absorptiometry in two subtypes of autosomal dominant osteopetrosis (ADO). Both types have been radiologically characterized by diffuse symmetrical osteosclerosis, but with characteristic differences. Increased thickness of the cranial vault is a typical finding in type I ADO, whereas endobones in the pelvis and end-plate thickening in the spine are obligate findings in type II. Eleven patients with type I from three kindreds, and seven patients with type II, one family participated in the study, and were compared with 18 age- and sex-matched normal controls. Whole-body BMC and BMD were measured, and regions of special interest were selected: head, axial, and appendicular skeleton. Moreover, lumbar spine and femoral neck scans were performed. Whole-body BMC and BMD, mostly reflecting cortical bone, were markedly increased in both types compared with normals. A pronounced osteosclerosis was present in the axial as well as the appendicular skeleton. Median BMD was markedly increased in the axial skeleton by 51% (44-56) and 42% (33-56), (median differences with 95% CI), respectively, for types I and II compared to normal controls, and in the appendicular skeleton by 48% (37-59) and 38% (16-45). No overlap between observed ranges of patients and controls was observed. A positive correlation between age and whole-body BMD was demonstrated in ADO, but not in the control group, indicating progressive osteosclerosis with age. Median BMD of the lumbar spine, which mostly reflects trabecular bone, showed increased densities in both types, 71% (51-84) and 59% (37-93), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Metabolic remission with octreotide in patients with insulinoma

OBJECTIVES

The efficacy of octreotide was studied in a group of patients with biochemical evidence of insulinoma.

DESIGN

A phase-II study.

SETTING

A university department of internal medicine.

SUBJECTS

Seven patients with biochemical evidence of insulinoma and without metastatic lesions.

INTERVENTION

Daily treatment with octreotide, a somatostatin analogue, mainly within the dosage of 100-300 micrograms day-1. The treatment was continued in patients with biochemical evidence of response or until surgery was undertaken.

MAIN OUTCOME

Five patients avoided hypoglycaemic symptoms and had normalization of blood glucose values for a median of 15+ months (range 0.2-54 months). Two did not improve metabolically. The treatment was well tolerated and had no deleterious effects on blood glucose regulation.

CONCLUSION

Octreotide seems to be a promising treatment for many of the patients with insulinoma who are not suitable for surgery.

Drug related hospital admissions. Results from an intervention program

As part of a high-intensity monitoring study of drug events as the cause of admission to departments of internal medicine, the effect of an educational intervention programme was studied. Two departments were included, one specialising in geriatrics and one that received patients by non-selected referral. The series consisted of 607 consecutive admissions studied before and 703 after the intervention. The drug events considered were adverse drug reactions and dose-related therapeutic failures, mainly due to non-compliance. A modest, statistically non-significant decrease in drug related hospital admissions (DRH) was seen, from 14% before to 13% after the intervention period. However, DRHs classified as definitely avoidable showed the significant decrease of 83%. There was no apparent relationship between the topics selected for the intervention programme and changes in the pattern of DRHs. No relationship between alterations in sales data and hospital admissions caused by a given drug could be demonstrated. A blinded external evaluation of case abstracts did not disclose any significant shift in the investigators' assessments. The intervention may have had an non-specific effect on avoidable DRHs.

Biological description of the cortisol responses to corticotropin-releasing-hormone (CRH) stimulation. An optimization and simplification of the test

For the corticotropin-releasing-hormone stimulation test the number of samplings and measurements are reduced to two--and the ratio between concentrations at 60 min and 0 min is calculated. The difference between the information given by absolute concentrations and ratio is negligible, but by using ratio, the influence of bias is eliminated. The test becomes simpler and the costs are reduced. The use of only two measurements facilitates the evaluation of quality specifications.

Lack of effect of mianserin on the symptoms of diabetic neuropathy

The effect of the non-tricyclic antidepressant mianserin on symptoms of diabetic neuropathy has been studied in 18 patients in a double-blind, cross-over study with imipramine as a positive control. The patients were treated with placebo, mianserin, and imipramine, each for two weeks, in randomized order, with 1-3 weeks between the treatments. The symptoms were assessed by observer and self-rating scales. Mianserin was given in the fixed dosage of 60 mg per day, whereas the dose of imipramine was adjusted to yield the optimal plasma concentration of imipramine plus desipramine of 400-600 nmol.l-1. The mianserin plus desmethylmianserin plasma concentration ranged from 85 to 850 nmol.l-1, with the highest concentration in a patient who was a poor metabolizer of both sparteine and mephenytoin. The symptoms of neuropathy were significantly reduced during imipramine treatment, although somewhat less than in earlier studies. In contrast, mianserin produced no change in symptoms in comparison with placebo. As there was no evidence that higher mianserin (plus metabolite) steady-state concentrations were associated with a more favourable effect, the negative outcome appeared not to be related to underdosing with mianserin. In contrast to drugs with documented effects on the symptoms of diabetic neuropathy, mianserin has a very weak or no inhibitory effect on 5-HT and noradrenaline reuptake and this may explain its poor clinical effect.

Drug-related illness as a cause of admission to a department of respiratory medicine

Three hundred and thirteen consecutive admissions to a department of respiratory medicine were evaluated in a prospective high-intensity monitoring scheme concerning adverse drug reactions or dose-related therapeutic failures as the contributing or sole cause of hospital admission. Eleven patients [3.5%, 95% confidence interval (CI) 2.0-6.2] were admitted because of adverse drug reactions. Only 3 of these patients manifested respiratory symptoms, while the remainder had various intercurrent nonpulmonary problems and were well known in the outpatient clinic, e.g. asthma or cancer patients. It is concluded that adverse drug reactions requiring admission rarely present as respiratory symptoms. Fourteen patient (4.5%, CI 2.7-7.4) were admitted because of dose-related therapeutic failures in all cases, except 2 with respiratory symptoms. Half of these were due to noncompliance. Analysis of theophylline samples taken on admission from 46 patients showed 25 (54%) to have concentrations below the therapeutic range of 55-110 microM, but contributed little to the identification of noncompliant patients. Eighty-three percent of the drug events were found to have been unavoidable. Nine patients admitted with acute asthma did not receive corticosteroids prior to admission (2.9%), all of which had therapy prescribed in general practice. The present study showed a comparatively low and hardly affectable prevalence of admissions caused by adverse drug reactions and dose-related therapeutic failure. However, therapeutic failure due to inappropriate choice of asthma medication, which was not included in this estimate, may be an important avoidable cause of admissions.

Drug related admissions to medical wards: a population based survey

1. In total 1999 consecutive admissions to six medical wards were subjected to a prospective high-intensity drug event monitoring scheme to assess the extent and pattern of admissions caused by adverse drug reactions (ADRs) or dose related therapeutic failures (TF), in a population-based design. The wards were sub-specialised in general medicine, geriatrics, endocrinology, cardiology, respiratory medicine and gastroenterology. 2. Considering definite, probable and possible drug events, the prevalence of drug related hospital admissions was 11.4% of which 8.4% were caused by ADRs and 3.0% by TFs. There were large inter-department differences. 3. The six classes of drugs most frequently involved in admissions caused by ADRs were anti-rheumatics and analgesics (27%), cardiovascular drugs (23%), psychotropic drugs (14%), anti-diabetics (12%), antibiotics (7%), and corticosteroids (5%). Noncompliance accounted for 66% of the TFs with diuretics and anti-asthmatics most frequently involved. 4. The pattern of drugs involved in ADRs was compared with the regional drug sales statistics. Drugs with a particularly high rate of ADR related admissions per unit dispensed were nitrofurantoin and insulin (617 and 182 admissions per 1,000,000 defined daily doses), while low rates were seen for diuretics and benzodiazepines (10 and 7 admissions per 1,000,000 defined daily doses). Confidence intervals were wide. 5. Patients who had their therapy prescribed by a hospital doctor had a slightly higher prevalence of drug events than those who were treated by a general practitioner (12.6% vs 11.8%). The reverse applied for drug events assessed as avoidable (3.3% vs 4.6%). Although these differences were not statistically significant, it may suggest general practitioners as the appropriate target for interventive measures.(ABSTRACT TRUNCATED AT 250 WORDS)

Drug related events and drug utilization in patients admitted to a geriatric hospital department

Two hundred ninety-four consecutive admissions to a geriatric department were evaluated for drug events as cause of admission. The drug events considered were adverse drug reactions (ADRs) and dose-related therapeutic failures. In 39 cases (13.3%), a definite, probable or possible drug event was a dominant or contributing cause of the admission (11.2% ADRs and 2.0% dose-related therapeutic failures). Five of these cases (1.7%) were judged to be due to errors in prescription and a further seven (2.4%) were found to have been avoidable by efforts exceeding the obligatory. There were no statistically significant differences between drug-related and non-drug related admissions in terms of age, sex, number of drugs taken at the admission or duration of hospitalization. ADRs in the geriatric patients are difficult to recognize and may be interpreted as senile loss of function. Sixty-seven percent of the patients took drugs with a sedative action, 68% took drugs with a hypotensive action, 67% took drugs with a potential for confusional states, 15% took drugs with a potential for depression, and 64% took drugs with a potential for constipation. A reduction of the number of drug-related hospital admissions by means of a large-scale intervention would be a difficult task for several reasons: no particular class of drugs caused the drug events, no particular mechanism dominated, no particular group of doctors were responsible for the drug events, and only a part of the drug events were judged to be avoidable.

Concentration-response relationship in paroxetine treatment of diabetic neuropathy symptoms: a patient-blinded dose-escalation study

A single-blind dose-escalation study with the selective serotonin reuptake inhibitor paroxetine was conducted in 19 diabetic patients with neuropathy symptoms. The effect of treatment was evaluated by self-rating using visual analog scales. After an initial placebo period, paroxetine doses were increased from 10 mg/day in 10 mg steps, until the dose was 30-70 mg/day. In all except four patients, there was a marked relief of symptoms. Plasma concentrations of paroxetine above 300-400 nM were required to insure maximal relief in the majority of patients responding on paroxetine, but a considerable interindividual variation was observed (10-800 nM, median of 195 nM). The therapeutic effect appeared to increase gradually as the plasma concentration increased. The great interindividual variation in the pharmacokinetics of paroxetine was confirmed, but as the effect is maximal within approximately 1 week, and the drug is nontoxic, it may be clinically feasible simply to titrate the dose from 20 mg/day until the maximal effect is achieved. However, it is advised that titration to an effect, in diabetic neuropathy using doses above 50 mg/day, be undertaken with care as there is limited experience with doses above this level in any population. The beneficial effect of paroxetine appeared to be maintained unaltered during an additional 1 month open-label treatment on optimal paroxetine doses.

Drug-related admissions to a department of medical gastroenterology. The role of self-medicated and prescribed drugs

Three hundred and twenty-eight consecutive patients admitted to a department of medical gastroenterology were evaluated in a high-intensity study of drug-related hospitalizations (DRH). The drug events considered were adverse drug reaction and dose-related therapeutic failures (DTF). With regards to the 'definite' and 'probable' drug events, DRHs accounted for 26 admissions (7.9%; 95% confidence interval (CI), 5.2-11.4%), and with the additional inclusion of 'possible' drug events DRHs accounted for 39 admissions (11.9%; CI, 8.6-15.9%). Of these, five and seven admissions, respectively, were caused by DTF. Patients admitted because of drug events took significantly more drugs than others. An evaluation of the circumstances of the 26 'definite' or 'probable' DRH showed none to be 'definitely avoidable', 6 to be 'possibly avoidable', and 20 to be 'not avoidable' by efforts from the prescribing physicians. Gastroduodenal lesions causally related to non-steroidal anti-inflammatory drug (NSAID) or aspirin use accounted for 17 of the definite, probable, or possible DRHs (44%). Only 1 of the 11 cases related to NSAID use was rated as possibly avoidable by efforts from the health service personnel. In 13 cases self-medication with aspirin played a substantial role in the DRH. Self-medication was largely characterized by poor indication, uncontrolled use, polypharmacy, treatment of epigastric pain with aspirin, and the patient's unawareness of potential adverse reactions. This suggests the need for intensified information to the public concerning the adverse effects of aspirin and NSAID.

Decreased thyroid hormone-stimulated oxygen consumption and glucose uptake in mononuclear blood cells from patients with autosomal dominant osteopetrosis type I

Nine patients, from four different families, with autosomal dominant osteopetrosis were investigated. They all had roentgenological type I disease, characterized by universal, symmetrical osteosclerosis and enlarged thickness of the cranial vault. All patients appeared clinically euthyroid. Thyroxine (T4) and tri-iodothyronine (T3) induced oxygen consumption and glucose uptake were studied in vitro in mononuclear blood cells from patients and control persons. Unstimulated oxygen consumption from patients and controls did not differ, and no difference in unstimulated glucose uptake was observed. The increase in T4 and T3 stimulated oxygen consumption was significantly lower in cells from patients with osteopetrosis (T4: 0.007 +/- 0.004 mumol/mg DNA per h, T3: 0.011 +/- 0.004 mumol/mg DNA per h) compared with controls (T4: 0.017 +/- 0.003 mumol/mg DNA per h, T3: 0.023 +/- -0.013 mumol/mg DNA per h; p less than 0.05, p less than 0.05). Cellular glucose uptake after T4 and T3 stimulation was significantly lower in patients (T4: 0.032 +/- 0.017 mmol/l per mg DNA per h, T3: 0.02 +/- 0.017 mmol/l per mg DNA per h) compared with controls (T4: 0.09 +/- 0.017 mmol/l per mg DNA per h, T3: 0.08 +/- 0.01 mmol/l per mg DNA per h; p less than 0.05, p less than 0.01). The reduced oxygen consumption and glucose uptake indicate thyroid hormone resistance which may be of pathogenetic importance for the development of autosomal dominant osteopetrosis type I.

Clomipramine vs desipramine vs placebo in the treatment of diabetic neuropathy symptoms. A double-blind cross-over study

1. The effect of clomipramine and desipramine on diabetic neuropathy symptoms was examined in a double-blind, randomised, placebo controlled, cross-over study for 2 + 2 + 2 weeks. Drug doses were adjusted according to the sparteine phenotype, i.e. extensive metabolisers were treated with 75 mg clomipramine day-1 and 200 mg desipramine day-1 whereas poor metabolisers were treated with 50 mg day-1 of both drugs. Nineteen patients completed the study. 2. Plasma concentration of clomipramine plus desmethylclomipramine was 70-510 nM in extensive metabolisers, vs 590 and 750 nM in two poor metabolisers. Desipramine levels were 130-910 nM, vs 860 and 880 nM. 3. Both clomipramine and desipramine significantly reduced the symptoms of neuropathy as measured by observer- and self rating in comparison with placebo. Clomipramine tended to be more efficacious than desipramine. Patients with a weak or absent response on clomipramine had lower plasma concentrations (clomipramine plus desmethyl-clomipramine less than 200 nM) than patients with a better response. For desipramine a relationship between plasma concentration and effect was not established. 4. Side effect ratings did not differ for clomipramine and desipramine and on both drugs three patients withdrew due to side effects. 5. Compared with earlier results obtained with imipramine dosed on the basis of plasma level monitoring, clomipramine and desipramine on fixed doses appeared less efficacious whereas the side effect profiles were the same. At least for clomipramine, appropriate dose adjustment on the basis of plasma level monitoring may increase the efficacy.

Drug related admissions to a cardiology department; frequency and avoidability

Three hundred and sixty-six consecutive patients admitted to a department of cardiology were evaluated for drug events as a cause of admission. The drug events considered were adverse drug reactions (ADR) and dose-related therapeutic failures (DTF). 'Definite' or 'probable' drug events accounted for 15 admissions (4.1%, 95% confidence limits 2.3-6.7%), of which eleven were ADR and four were DTF. With the inclusion of six 'possible' drug events, the rate of drug-related hospitalizations (DRH) was 5.7%. DRHs were characterized by a preponderance of acute admissions and elderly patients. Hypokalaemia (less than 3.5 mM) was observed in 27 (16%) patients receiving diuretics, and could be related to four cases of arrhythmias (two 'probable' and two 'possible' ADR). The average serum potassium level was similar in diuretic treated patients with or without drugs to counteract hypokalaemia, irrespective of the drugs chosen. Among the 15 'definite'/'probable' DRHs, five were considered to be due to an error in prescription, and a further five cases were judged to have been avoidable had appropriate measures been taken by prescribing physicians. A DRH educational intervention programme should primarily deal with non-compliance or with prescription of diuretics or digoxin, since these problems constitute the majority of cases of DRH. No specific group of doctors could be targeted as responsible for DRH, avoidable or not.

Drug related hospital admissions: the role of definitions and intensity of data collection, and the possibility of prevention

Three hundred and thirty-three consecutive patients in a medical ward were evaluated in a high-intensity monitoring scheme for drug events as a cause of hospitalization. Taking into consideration only 'definite' and 'probable' drug events, we found 36 cases (10.8%) of all admissions to be drug-related hospitalizations (DRH). Of these, 8.1% were adverse drug reactions and 2.7% were therapeutic failures due to ineffective dosage. In 8 cases (2.4%) the drug event could definitely have been avoided, and a further 13 cases (3.9%) were considered to have been potentially avoidable if appropriate measures had been taken by the health service. In 19 cases (53%) the referring physician was unaware of the drug-related problem. Those patients admitted because of a drug event were taking significantly more drugs than other individuals. The avoidable drug events pointed to the primary health care physicians as the appropriate targets for preventive measures in terms of intensified drug education. The study demonstrated that a reliable estimate of the DRH rate requires active data collection by a qualified health service worker in close collaboration with the patient's family doctor in cases of suspected DRH.

Autosomal dominant osteopetrosis (a family study)

Osteopetrosis is a rare metabolic disorder, characterized by an abnormal accumulation of bone mass probably caused by diminished bone resorption. Symptoms are directly and indirectly derived from the increased amount of bone. A family study was made, starting with a proband presenting with symptoms of trigeminal neuralgia. The pedigree indicated an autosomal dominant inheritance through three generations, comprising four affected subjects, of whom two were free of symptoms.